Production of Al-Mg-transition element alloys

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Measuring consumer detriment under conditions of imperfect information

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Sampling-Based Query Re-Optimization

Despite of decades of work, query optimizers still make mistakes on "difficult" queries because of bad cardinality estimates, often due to the interaction of multiple predicates and correlations in the data. In this paper, we propose a low-cost post-processing step that can take a plan produced by the optimizer, detect when it is likely to have made such a mistake, and take steps to fix it. Specifically, our solution is a sampling-based iterative procedure that requires almost no changes to the original query optimizer or query evaluation mechanism of the system. We show that this indeed imposes low overhead and catches cases where three widely used optimizers (PostgreSQL and two commercial systems) make large errors.Comment: This is the extended version of a paper with the same title and authors that appears in the Proceedings of the ACM SIGMOD International Conference on Management of Data (SIGMOD 2016

Kepler-210: An active star with at least two planets

We report the detection and characterization of two short-period, Neptune-sized planets around the active host star Kepler-210. The host star's parameters derived from those planets are (a) mutually inconsistent and (b) do not conform to the expected host star parameters. We furthermore report the detection of transit timing variations (TTVs) in the O-C diagrams for both planets. We explore various scenarios that explain and resolve those discrepancies. A simple scenario consistent with all data appears to be one that attributes substantial eccentricities to the inner short-period planets and that interprets the TTVs as due to the action of another, somewhat longer period planet. To substantiate our suggestions, we present the results of N-body simulations that modeled the TTVs and that checked the stability of the Kepler-210 system.Comment: 8 pages, 8 Encapsulated Postscript figure

Putrescine stimulates chemiosmotic ATP synthesis

AbstractPutrescine is a main polyamine found in animals, plants and microbes, but the molecular mechanism underlying its mode of action is still obscure. In vivo chlorophyll a fluorescence in tobacco leaf discs indicated that putrescine treatment affects the energization of the thylakoid membrane. Molecular dissection of the electron transport chain by biophysical and biochemical means provided new evidence that putrescine can play an important bioenergetic role acting as a cation and as a permeant natural buffer. We demonstrate that putrescine increases chemiosmotic ATP synthesis more than 70%. Also a regulation of the energy outcome by small changes in putrescine pool under the same photonic environment (i.e., photosynthetically active radiation) is shown. The proposed molecular mechanism has at least four conserved features: (i) presence of a membrane barrier, (ii) a proton-driven ATPase, (iii) a ΔpH and (iv) a pool of putrescine

Lifetime alcohol use disorder and gambling disorder: Clinical profile and treatment response

Objectives: Gambling disorder affects 0.5-2.4% of the population and shows strong associations with lifetime alcohol use disorder. Very little is known regarding whether lifetime alcohol use disorder can impact the clinical presentation or outcome trajectory of gambling disorder. Methods: Data were pooled from previous clinical trials conducted on people with gambling disorder, none of whom had current alcohol use disorder. Demographic and clinical variables were compared between those who did versus did not have lifetime alcohol use disorder. Results: Of the 621 participants in the clinical trials, 103 (16.6%) had a lifetime history of alcohol use disorder. History of alcohol use disorder was significantly associated with male gender (relative risk [RR] = 1.42), greater body weight (Cohen's D = 0.27), family history of alcohol use disorder in first-degree relative(s) (RR = 1.46), occurrence of previous hospitalization due to psychiatric illness (RR = 2.68), and higher gambling-related legal problems (RR = 1.50). History of alcohol use disorder was not significantly associated with other variables that were examined, such as severity of gambling disorder or extent of functional disability. Lifetime alcohol use disorder was not significantly associated with the extent of clinical improvement in gambling disorder symptoms during the subsequent clinical trials. Conclusions: These data highlight that lifetime alcohol use disorder is an important clinical variable to be considered when assessing gambling disorder because it is associated with several untoward features (especially gambling-related legal problems and prior psychiatric hospitalization). The study design enabled these associations to be disambiguated from current or recent alcohol use disorder.</p

Low-Light Image Enhancement Based on U-Net and Haar Wavelet Pooling

The inevitable environmental and technical limitations of image capturing has as a consequence that many images are frequently taken in inadequate and unbalanced lighting conditions. Low-light image enhancement has been very popular for improving the visual quality of image representations, while low-light images often require advanced techniques to improve the perception of information for a human viewer. One of the main objectives in increasing the lighting conditions is to retain patterns, texture, and style with minimal deviations from the considered image. To this direction, we propose a low-light image enhancement method with Haar wavelet-based pooling to preserve texture regions and increase their quality. The presented framework is based on the U-Net architecture to retain spatial information, with a multi-layer feature aggregation (MFA) method. The method obtains the details from the low-level layers in the stylization processing. The encoder is based on dense blocks, while the decoder is the reverse of the encoder, and extracts features that reconstruct the image. Experimental results show that the combination of the U-Net architecture with dense blocks and the wavelet-based pooling mechanism comprises an efficient approach in low-light image enhancement applications. Qualitative and quantitative evaluation demonstrates that the proposed framework reaches state-of-the-art accuracy but with less resources than LeGAN